Target heart rate

The Target Heart Rate (THR), or Training Heart Rate, is a desired range of heart rate reached during aerobic exercise which enables one's heart and lungs to receive the most benefit from a workout. This theoretical range varies based on one's physical condition, gender, and previous training. Below are two ways to calculate one's Target Heart Rate. In each of these methods, there is an element called "intensity" which is expressed as a percentage. The THR can be calculated as a range of 65%–85% intensity. However, it is crucial to derive an accurate HR_max to ensure these calculations are meaningful (see above).

Example for someone with a HR_max of 180 (age 40, estimating HR_max as 220 − age):
65% intensity: (220 − (age = 40)) × 0.65 → 117 bpm
85% intensity: (220 − (age = 40)) × 0.85 → 153 bpm

Karvonen method

The Karvonen method factors in Resting Heart Rate (HR_rest) to calculate Target Heart Rate (THR), using a range of 50%–85%:

THR = ((HR_max − HR_rest) × %Intensity) + HR_rest

Example for someone with a HR_max of 180 and a HR_rest of 70:
50% intensity: ((180 − 70) × 0.50) + 70 = 125 bpm
85% intensity: ((180 − 70) × 0.85) + 70 = 163 bpm

Zoladz method

An alternative to the Karvonen method is the Zoladz method, which derives exercise zones by subtracting values from HR_max.

THR = HR_max – Adjuster ± 5 bpm

Zone 1 Adjuster = 50 bpm

Zone 2 Adjuster = 40 bpm

Zone 3 Adjuster = 30 bpm

Zone 4 Adjuster = 20 bpm

Zone 5 Adjuster = 10 bpm

Example for someone with a HR_max of 180:
Zone 1 (easy exercise) : 180 − 50 ± 5 → 125 – 135 bpm
Zone 4 (tough exercise): 180 − 20 ± 5 → 155 – 165 bpm